The files were tagged with a tracker so Bitglass could obtain some technical data on systems that accessed it. They also created a fake banking site portal.

The experiment simulated what would happen if a person was "phished," or had their online credentials stolen in some kind of trick or cyberattack. Bitglass leaked the details to so-called Dark Web websites where cybercriminals mingle.

Unsurprisingly, the Google Drive credentials were used fairly quickly. Bitglass said there were three attempted logins to Google Drive in the first day and five attempted logins to the fake bank site.

Within two days, files were downloaded from the Google Drive account. Most of those who accessed Google Drive also tried to use the same credentials for the victim's other online accounts.

Twelve percent of those who accessed Google Drive tried to download the sensitive files there, and one also managed to crack an encrypted file.

Bitglass conducted a similar experiment a year prior where it found that people accessing the tagged documents rarely used the anonymity network Tor, short for the The Onion Router.

This year, however, 68 percent of those who accessed the Google Drive account used Tor. Still, that leaves more than a third who didn't take any protections to mask their real IP address, which means they're more likely to be traced.

The finding demonstrates that "hackers are becoming more security conscious and know to mask their IPs when possible to avoid getting caught," the company said.

Of the systems that did not use Tor, 35 percent of the logins came from Russia, with about 16 percent in the U.S. and 3.5 percent from China, Bitglass said.